1. Field of the Invention
The present invention relates to an improvement in a camera with an image stabilizing device which prevents image blur due to vibration of a hand of a photographer.
2. Related Background Art
In a prior art camera with an image stabilizing device, a swing displacement detection means for detecting an angular displacement relative to an absolute space as a swing displacement of the camera, and a correcting optical system, is driven in accordance with an output of the swing detection means in order to correct the image blur thus aiding an imaging optical system. The correcting optical system may use a variable vertical angle prism which utilizes a refractive index of liquid as disclosed in Japanese Laid-Open Patent Application No. 2-59718. It supplies a current which is proportional to the output of the swing detection means to a driving voice coil of the variable vertical angle prism. (In actuality, a feedback control is effected to make the output of the swing detection means and an angular displacement output of the variable vertical angle prism equal to each other.)
Accordingly, in the actual control of the camera, the energization of the voice coil is usually started before a shutter is opened, and the voice coil is deenergized a predetermined period of time after the closure of the shutter.
However, in the above prior art camera, since the shutter driving coil of the camera and the voice coil for driving the correcting optical system are simultaneously energized, if a voltage of a battery cell mounted in the camera drops, the operation may be assured by a normal battery check but the correct opening operation of the shutter may not be assured because the actual supply current is very large due to the fact that the current to drive the correcting optical system is additionally required during the shutter opening operation.
On the other hand, if the battery check level is set to a higher level to assure the energizations to both the shutter driving coil and the voice coil for the correcting optical system, the number of frames to be photographed is very much reduced compared with a normal case.